To investigate the activity of chemotherapeutic agents in advanced prostatic cancer, specifically cyclophosphamide, procarbazine, imidazole carboxamide (DTIC), estramustine phosphate and prednisolone mustard (Leo-1031). To determine if sequential and combination therapy with these agents is useful clinically. To demonstrate their therapeutic effectiveness against standard therapy, specifically diethylstilbestrol (DES) and/or bilateral orchiectomy. To determine the predictive value of the in vitro evaluation of chemotherapeutic agents (5-alpha reductase, arginase, DNA synthesis). To participate in all current and future protocols of the Treatment Subcommittee of the National Prostatic Cancer Project.